Commit Graph

9 Commits (ca08e316af04b76c217c6c338d4043f158dd874c)

Author SHA1 Message Date
Joe Tsai 2e5d08ec4f
net/connstats: invert network logging data flow (#6272)
Previously, tstun.Wrapper and magicsock.Conn managed their
own statistics data structure and relied on an external call to
Extract to extract (and reset) the statistics.
This makes it difficult to ensure a maximum size on the statistics
as the caller has no introspection into whether the number
of unique connections is getting too large.

Invert the control flow such that a *connstats.Statistics
is registered with tstun.Wrapper and magicsock.Conn.
Methods on non-nil *connstats.Statistics are called for every packet.
This allows the implementation of connstats.Statistics (in the future)
to better control when it needs to flush to ensure
bounds on maximum sizes.

The value registered into tstun.Wrapper and magicsock.Conn could
be an interface, but that has two performance detriments:

1. Method calls on interface values are more expensive since
they must go through a virtual method dispatch.

2. The implementation would need a sync.Mutex to protect the
statistics value instead of using an atomic.Pointer.

Given that methods on constats.Statistics are called for every packet,
we want reduce the CPU cost on this hot path.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 2327c6b05f
wgengine/netlog: preserve Tailscale addresses for exit traffic (#6165)
Exit node traffic is aggregated to protect the privacy
of those using an exit node. However, it is reasonable to
at least log which nodes are making most use of an exit node.

For a node using an exit node,
the source will be the taiscale IP address of itself,
while the destination will be zeroed out.

For a node that serves as an exit node,
the source will be zeroed out,
while the destination will be tailscale IP address
of the node that initiated the exit traffic.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 48ddb3af2a
wgengine/netlog: enforce hard limit on network log message sizes (#6109)
This is a temporary hack to prevent logtail getting stuck
uploading the same excessive message over and over.
A better solution will be discussed and implemented.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai a3602c28bd
wgengine/netlog: embed the StableNodeID of the authoring node (#6105)
This allows network messages to be annotated with which node it came from.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 81fd259133
wgengine/magicsock: gather physical-layer statistics (#5925)
There is utility in logging traffic statistics that occurs at the physical layer.
That is, in order to send packets virtually to a particular tailscale IP address,
what physical endpoints did we need to communicate with?

This functionality logs IP addresses identical to
what had always been logged in magicsock prior to #5823,
so there is no increase in PII being logged.

ExtractStatistics returns a mapping of connections to counts.
The source is always a Tailscale IP address (without port),
while the destination is some endpoint reachable on WAN or LAN.
As a special case, traffic routed through DERP will use 127.3.3.40
as the destination address with the port being the DERP region.

This entire feature is only enabled if data-plane audit logging
is enabled on the tailnet (by default it is disabled).

Example of type of information logged:

	------------------------------------  Tx[P/s]    Tx[B/s]  Rx[P/s]   Rx[B/s]
	PhysicalTraffic:                       25.80      3.39Ki   38.80     5.57Ki
	    100.1.2.3 -> 143.11.22.33:41641    15.40      2.00Ki   23.20     3.37Ki
	    100.4.5.6 -> 192.168.0.100:41641   10.20      1.38Ki   15.60     2.20Ki
	    100.7.8.9 -> 127.3.3.40:2           0.20      6.40      0.00     0.00

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai c21a3c4733
types/netlogtype: new package for network logging types (#6092)
The netlog.Message type is useful to depend on from other packages,
but doing so would transitively cause gvisor and other large packages
to be linked in.

Avoid this problem by moving all network logging types to a single package.

We also update staticcheck to take in:

	003d277bcf

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai a1a43ed266
wgengine/netlog: add support for magicsock statistics (#5913)
This sets up Logger to handle statistics at the magicsock layer,
where we can correlate traffic between a particular tailscale IP address
and any number of physical endpoints used to contact the node
that hosts that tailscale address.

We also export Message and TupleCounts to better document the JSON format
that is being sent to the logging infrastructure.

This commit does NOT yet enable the actual logging of magicsock statistics.
That will be a future commit.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai f9120eee57
wgengine: start network logger in Userspace.Reconfig (#5908)
If the wgcfg.Config is specified with network logging arguments,
then Userspace.Reconfig starts up an asynchronous network logger,
which is shutdown either upon Userspace.Close or when Userspace.Reconfig
is called again without network logging or route arguments.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 1b4e4cc1e8
wgengine/netlog: new package for traffic flow logging (#5864)
The Logger type managers a logtail.Logger for extracting
statistics from a tstun.Wrapper.
So long as Shutdown is called, it ensures that logtail
and statistic gathering resources are properly cleared up.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago